Ladder truck



pril 12, 1938. H. M. HAvENs LADDER TRUCK Filed April 25, 1955 4Sheets-Sheet l Srmentor HUMER M.HAVENS f gli (Ittorneg 5 April l2, 1938'H. M. HAVENS 2,114,262

LADDER TRUCK Filed April 25, 1955 4 sheets-sheet 2 76 (f o l m 7s 73 El50 7g f1.5 f o u l 1| O O o www I6 I l l5 nnenfor m93' 3 HUMER NLHAVENS(Ittorneg 5 April 12, 193s. H M, HAVENS 2,114,262

LADDER TRUCK Filed April 23, 1935 4 Sheets-Sheet 3 Srmentor ynMER M.HAvENs Bg @M (Ittorneg .1

April 12, 1938. H. M HAVENS 2,114,262

LADDER TRUCK Filed April 25, 1935 4 Sheets-Sheet 4 mnentor HUMERM.HAVENS y Wx (lttorneg J Patented Apr. l2, 1938 UNITED- STATESI PATENToFFicE LADDER Tanon Homer M. Havens, Columbus, Ohio, assignor to TheSeamve Comration, Columbus, Ohio, a

corporation o f Michigan l Application April 23, 1935, Serial No. 17,835

SCiaims.

'This invention relates to aerial ladders such as used by the firedepartments of municipalities to aid in extinguishing res and rescuingpersons and property from burning buildings.

Such ladders are now commonly transported by engine driven trucks.

Because such ladders and the, essential parts thereof are necessarilyheavy and bulky and therefore dimcult to quickly move, the primaryobject of the invention is to provide improvements in details ofconstruction whereby their operations are facilitated and speede'd bythe application of the power used to transport the ladder and therebyrelieve the ladder men of the physical exertion heretofore necessary inthe handling oi' such parts. 'Ihe particular object of the invention isto provide improved means whereby flexible hose for conducting pressuresis dispensed with so that the turn table in such structure may berotated in either 'direction as much as desired. Other objects willappear from the disclosure herein.

In the accompanying drawings showing one exempliiication of theinvention- 1 Figure 1 is a general view in sideelevation and partlydiagrammatic onv a relatively small scale illustrating a fraction of atruck with a turntable thereon supporting the ladder and the powerapplying means whereby the ladder is raised and lowered.

Fig. 2 is a detail on a largergscale partly in` section and elevationillustrating the mounting and connection of the parts for applying powerto raise and lower the ladder.

Fig. 3 is a detail partly in section and showing .means to operate theladder extensions.

Fig. 4 is a detail view partly in elevation and partly in section of themeans for rotating the turn-table and for hoisting the ladderextensions. f

Fig. 5 is a detail view in rear elevation of means for locking theturn-table in the position to which it'may be rotated.

Fig. 6 is a plan view with parts in section of the means for controllingthe operation of the ladder. i

Fig, 'I is a detail plan and sectional view of the operating andcontrolling means for the hoisting of the ladder extensions.

Fig. 8 is detail view of the base of the ladder to show portions of themeans for hunting the raising of the ladder.

In the views I6 designates the truck bed of the chassis and I I the.turn-table which is supported centrally to be rotated on said truck bed.The turn-table II is`engagedand supported at its rim on the truck bed bya suitable "track I3 withv ball bearings; and at the center of theturn-table is secured la double valve structure supported on a ring Ilin which latter is supported a non-rotatable casing I5. Saidnon-rotatable casing is provided with a threaded intake I6 having anupwardvpassage I6, the upper end of which communicates with the twovalve casings I'I and I6 for the purpose of supplying oil under pressureto raise and lower the ladder and also to turn a winding drumy toraiseand lower the ladder extensions.y The casing I5is provided with adistinct discharge downward passage I9SL surrounding said upward passageand leading to a threaded opening I9 for the return of the oil to thetank.

' 2iidesignates the main ladder, it being pivoted at its base on theopposite ends of a shaft 2l ljournaled in brackets 2|L rising from theLturn table. 'Ihe main ladder carries extensions 2lim andlib.

At each of its opposite sides the ladder is connected 'with theturn-table by a piston rod 22 having piston 22EL working in a cylinder23, said piston rod being pivoted to the ladder and said l cylinderpivoted to the turn-table so that wh'en liquid (preferably oil) isforced into the cylinder at the lower side of the piston the ladder israised on the shaft ends 2|, and when liquid is forced into the cylinderthrough a by-pass 24 to the upper side of the piston the ladder islowered. Each of the two valve, casings II-and I 8 contains a doubleslide valve, one to control the ow of oil in pipes 25 and 26. The pipe25 andits two branches 25 and 25b conduct the oil tothecylinder 2l forraising the ladder and pipe 26 and its two branches 26'l and 26b conductoil to the bypass 24 for lowering theladder. The two heads of each ofsaid valves are mounted on the opposite ends of a tube as at 21 carriedby the stem of the valve, said tube being closed between the heads, but-perforated as shown at 2lb at its opposite projecting ends to permitthe flow of oil through thetube between the chamber portions of thecasing beyond the valve heads.

The stems of valves 21 and 28 are each shifted by manual operation atthe housing 41 to open and close the ports to said pipes 25 and 26, butmeans are provided as hereinafter described for vautomatically closingthem upon predetermined operation.

The valve casings I1 and I8 and ring bearing the discharge I9 of thecasing I5 communicates with a storage tank 34 that in turn is connectedwith the intake ofthe pump 33. The pump 33 is of the usual rotating typeand is operated by the power take off shaft 35 from the engine 36 thatpropels the truck carrying the ladder to the site of a re. The engine ofthe truck referred to and the power take off are not shown in detailbecause they are of ordinary and well known construction. In thepressure delivering operation the same liquid (the oil) is repeatedlyused to,

raise the ladder or project the ladder extensions because after removingthe oil from the tank 34 to perform these operations it is returned tosaid tank through the discharge I9 of the stationary casing I5.

The valve casing I8 has connected communicatingly with it pipes 31 and38 for the purpose of conducting oil under pressure to a fluid motor forraising or lowering the ladder-extensions 2lia and 2Gb, said extensionsbeing connected in the usual manner for their concurrent movement. Saidextensions are operated by means of two cables (one shown at 39)connected to opposite ends of the drum to wind in opposite directions,one of said cables to draw up the extensions and the other to pull downsaid extensions according -to th direction of rotation of the drum.

The pipe 38 leads the oil under pressure from the control valve casingI8 to a port 38a (shown in broken lines Fig. 3) of a fluid motor 5I, andafter operating said motor to the extent desired the oil is returned tosaid valve casing I8 by means of the pipe 31 connected with the port 31Bof said motor 5I. Said operation occurs only when the pressure intakeand exhaust of the casing I8 are utilized.

Connected with the shaft 2l of the cable winding drum 58 is a worm gear40 driven by a worm 4I on the shaft of the motor 5I. By reason of thisconstruction said motor 5I can be driven to rotate the cable in theproper direction to cause the extending or drawing down of the ladderextensions. Change of rotation of the motor and winding drumisaccomplished by shifting the valve of the casing I8 to cause the oilunder pressure to flow through the pipe 31 or 38 according to thedirection of rotation necessary to achieve the operation desired. Thetwo points for attaching the cables to simultaneously wind and unwindthem are indicated at 50a and 58".

The two valve casings I1 and I8 have between them at 42 an intake commonto them for the pumped oil, said intake being connected by passages withthe intake I8 of the casing I5.

When oil is being pumped to raise the ladder the residual oil in thecylinder 23 above the piston therein is returned or exhausted to thetank 33 through the tube 21.1 connecting the valve heads of the valvecasing I1 through outlet I9 and down passage I9EL and outlet I9 in thecasing I5. And when the piston is shifted to cause the pressure to passthrough the by pass I6 in lowering the ladder the oil below the pistonin the cylinder exhausts directly through the outlet 44 and through thedown passages in the casing I5 to the tank 34. The operation is thesame'when raising and lowering the ladder extensions but is controlledby the valve of similar` construction in casing I8. By reason of thisconstruction theactuating medium'is saved for repeated use, and at thesame time provides a construction whereby the turn table can be turnedunrestrictedly in either direction at will.

The stems 21 and 28 for the valves in the casings I1 and I8 are forkedat their outer ends to receive a link 21d with one of two crank arms ona shaft 45 op rated by a handle 46 at the top of housing 41 containingthe controlling means` whereby said valves can be shifted to initiallydirect the flow of the oil pressure for the opera.-

Ation of raising the ladder and its extensions, but

it is desirable that said rising movement be automatically limited. Forthis purpose, and in the case of the ladder raising, the stem 21 isprovided with a collar 21c engaged by one arm 48 of a bell-crank lever49 pivoted on the turntable, the other arm of said lever being actuatedby a collar 52 on a rod 53 connected with one end of alink 54 having itsother end connected with an ear 55 on the base of the ladder so thatwhen the ladder has been raised to the predevtermined limit the oilpressure is cut off provided the valve stem has not been earliermanually shifted. And likewise in the case of theladder-extension-raising-means the valve stem 28 is provided with acollar 28c engaged by one end of a bell-crank lever pivoted on theturntable, the other arm of said lever being actuated by a collar 6I ona rack rod 62 riding on a pinion 63 on the shaft of a large worm gear 64driven by a worm 65 on the shaft of the 'motor that turns theladder-extension hoisting drum'50, so that when the ladder extensionshave been extended to the predetermined limit provided the valve in thecasing I8 has not been earlier manually shifted to cut off the flow ofthe oil pressure. It will be observed that the flow of pressure in thevalve casing I1 or I8 can be arrested by moving the valves therein toneutral position and the ladder or extensions thereof supported in anyposition to which moved by reason of the fluid entrapped in thecylinders or motor.

The means for rotating the turn-table includes the followingz-Thesupporting track I3 having its rim provided with gear teeth engaged byan intermediate gear wheel 10 so that in turn it is engaged by a pinion1I secured on the lower end of a vertical shaft 12 extended upward inthe housing 41 secured on a base on the turn-table. The upper end ofsaid shaft 12 has secured to it a bevel gear 14 that is engaged by apinion secured on a shaft- 15 turned by a hand wheel 16 so that byturning said wheel 16 in one direction or the other the turn-table canbeturned to the position desired and suitable for pointing the ladder andits extensions in the direction desired notwithstanding the position ofthe truck carrying the apparatus; When the ladder has been pointed, asdesired, the shaft of the hand wheel 16 can be locked to prevent anymovement of the table by means of a clevis 11 on said shaft drawntightly around said shaft by a cam 18 connected with a bolt and a handleoperating on the clevis to draw the free ends thereof together intopinching engagement with said shaft.

At 88 is an ordinary relief chamber to take care of excess pressure inthe oil system in case the ladder meets an obstruction either inraising 1. In a truck ladder, a turn-table mounted o i the truck, aladder pivoted on the turn-table, fluid pressure actuated means forraising and lowering the ladder, a valve casingsupported on theturn-table to rotate therewith and communicating with said means forraising and lowering the ladder, said valve casinghaving an intake and adischarge passage and containing a valve to control the application offluid pressure to said means for raising and lowering the ladder, apressure uid conducting casing supported stationarily on the truckcoaxially with the axis of rotation of said turn table, said stationarycasing having a fluid pressure intake and discharge passage distinct`from each other communicating in all positions of the turn-table withcorresponding passages in said control valve casing, a tank into whichthe outlet of said stationary casing discharges, and a pump for creatingfluid pressure through the intake of said stationary casing to the saidvalve casing and ladder raising and lowering means.

2. In a truck ladder, a turn-table mounted on the truck, a ladderpivoted on the turn-table, fluid pressure actuated means for raising andlowering the ladder, a valve casing supported on the turn-table torotate therewith and communicating with said means for raising andlowering the ladder., said valve casing having an intakev and adischarge passage and containing a valve to control the application ofiiuid pressure to said means for raising and lowering the ladder, apressure fluid conducting casing supported stationarily on 4the truckcoaxially with the axis of rotation of said turn-table, said stationarycasing having a fluid pressure intake and discharge passage distinctfrom each other communicating in all positions of the turn-table withcorresponding passages in said control valve casing, a. tank into whichthe outlet oi' said stationary casing discharges, a pump for creatingpressure through the intake of said stationary casing, and a conductorfor 'feeding the pressure medium from said tank to said pump.

3. In a ladder truck, a turn-table mounted on the truck and supportingthe main ladder and an extension thereon, a fluid pressure conductingcasing supported stationarily on the truck below said turn-table, saidcasing having an inlet and an outlet passage distinct from each other inrespect to a pressure supply means, two valve casings supported uponsaid turn-table to rotate therewith, said valve casings havingconcentric communication in all positions of the turn table with theinlet and outlet passages of said stationary casing, iiuid pressureactuated means communicatingly connected with said valve casings forraising and lowering the main ladder, and independently operable fluidpressure means communicatingly connected with said valve casings toextend or retract the ladder extension, and valve means in said valvecasings for controlling at will the application of fluid pressure tosaid main ladder and its extension.

4. In a ladder truck, a turn-table mounted on the truck and supportingthe main ladder and an extension thereon, a uid pressure conductingcasing supported stationarily on the truck beiowsaid turn-table, saidcasing having an inlet and an outlet passage in respect to a pressuresupply means distinct from each other, two valve \casings supported uponsaid turn-table, s aid valve casings swiveled to said stationarypressure conducting casing and having concentric communication with theinlet and outlet passages thereof, tluid pressure actuated meanscommunicatingly connected with said valve casings for raising andlowering the main ladder, andindependently operable iluid pressure meanscommunicatingly connected with said valve casings to extend or retractthe ladder extension, and valve means in s aid valve casings forcontrolling at will the application of iiuid pressure to saidl mainladder and its extension.

5.v In a ladder truck. a turn-table mounted on the truck and supportingthe main ladderhaiid an extension thereon, fluid pressure supplying andactuated means for said ladder and extension including ya fluid pressureconducting casing supported stationarily on the truck below saidturntable, said casing having an inlet and an outlet passage distinctfrom each other in respect to a pressure supply means, two valve casingssupported upon said turn-table, said valve'casings swiveled to saidstationary pressure conducting casing and having concentriccommunication with the inlet and outlet passages thereof, means forautomatically limiting the application of pressure to said fluidpressure actuated means communicatingly connected with said valvecasings for raising and lowering the main ladder,

` and independently operable fluid pressure applying meanscommunicatingly connected with said valve casings to extend or retractthe ladder f extension at will. 6. In a ladder truck, a turn-tablemounted on the truck and supporting the main ladder and an extensionthereon, a fluid pressure conducting casing supported stationarily onthe truck below said turn-table, said casing having an inlet and an'outlet passage distinct from each other in respect to a pressure supplymeans, two valve casings supported upon said turn-table, said valvecasings swiveled to said stationary pressure-conducting casing andhaving concentric communication with the inlet and outlet passagesthereof, packing means at the swiveling junction of said valve casingsand pressure conducting casing for preventing leakage of pressure iiuidto the atmosphere and from one passage to the other, fluid pressureactuated means communicatlngly connected with one of said valve casingsfor raising and lowering the main ladder, and independently operable uidpressure means communicatingly connected with theV other of said valvecasings to extend or retract the ladder extension, and valve means insaid valve casings for controlling at will the application of fluidpressure to said main ladder and its extension.

7. In a ladder truck, a turn-table mounted on the truck and supportingthe main ladder and an extension thereon, fluid pressure actuatablemeans for raising and lowering the main ladder and independentlyoperable iiuid pressure actuatable means including a fluid motor andgearing means actuated thereby for extending and retracting the ladderextension, two valve casings and means therein and connected therewithfor controlling at will the application vof fluid pressure to each ofsaid uid pressure actuatable means, a iiuid pressure conducting casingsupported stationarily on the truck, said casings having iluidpressure'inlet and outlet passages dissage distinct from each other inrespect to a pressure supply means, two valve casings supported upon theturn-table, said valve casings swiveled to said stationary pressureconducting casing and having coaxial communication with thc inlet andoutlet passages thereof, means for controlling the application ofpressure to said main and extension ladder, and means for automaticallylimiting the application of pressure to the extension ladder.

HOMER M. HAVENS.

